Thursday, August 29, 2013

Joshua Tree (Yucca brevifolia) and its sister species (Yucca jaegeriana)
are vegetative icons of the arid, continental climate region of the southwesterly
Mojave Desert floristic region. By contrast, as iconic are oak woodlands of
cismontane inverse – winter wet, maritime climate California. The two are exactly inverse.

Lenz (Aliso 24:97-104. 2007) admirably shows that there are clearly two
species of Joshua Tree – at this juncture neither taxon has been investigated
with molecular methods. The attached map is an approximation drawn
from Little (1976) – red is the distribution of Yucca brevifolia Engelmann and
green the distribution of Y. jaegeriana (McKelevy) L.W. Lenz.

The photograph is a site in Oak Creek Canyon, Kern County, in the Techachapi
Mountains (15 April 2003, ca. 35.03218 -118.39499) where Yucca brevifolia reaches its most mesic
incursion into, barely, cismontane California, thus barely within the
California Floristic Province sensu stricto.

Might these extreme western-most Joshua trees have something going for them in the genome
department?

Friday, August 23, 2013

Arctostaphylos manzanita ssp. roffii is one of 6 recognized
races of a common, often dominant, California manzanita. The 6 tetraploid races of Arctostaphylos manzanita largely have
allopatric geographic ranges. The
Roof manzanita is not a listed rare plant: it is a relatively uncommon
however, and is narrowly endemic to the Cascade and North Coast ranges, with one central Sierran exception (SBBG50844)

The Ponderosa fire burned about;25,000 acres of Tehama and Shasta County
in August, 2012. Areas where I had seen
and collected Arctostaphylos manzanita
ssp. wieslanderi before the fire, I had not understood the differences between the two subspecies. In the Ponderosa Fire, both were
burnt to a crisp. In May, 2013 I revisited one site, and observed Arctostaphylos manzanita ssp. roffii resprouting.

In the instance recorded here, resprouting did not occurring over the
entire burl. Rather, the only resprouts
were originating from below the soil (as seen at the 4 o’clock position on the
photo of the burl). In the present
instance, it appears as if the fire was sufficiently hot so as to completely
kill all of the exposed portion of the burl, leaving only the below ground
parts viable.

Resprouting dymanics of chaparral shrubs following fire, including
genetic signaling pathways and how they become activated, are a fertile subject
for study. Burn baby burn...

N.B. on the original post, dated 8/23/2013, I mis-identified these plants as A. manzanita ssp. wieslanderi. On April 11, 2014 I again visited the Ponderosa Fire region as part of my vegetation characterization studies, and confirmed that both infrataxa occur in the region. A. manzanita ssp. wieslanderi lacks a basal burl, while A. manzanita ssp. roffii has a huge burl. A. manzanita ssp. roffii is superficially similar to A. patula, which also lacks a basal burl (but does resprout epicormically after fire), and which occurs at higher elevations in the Battle Creek watershed.

Thursday, August 22, 2013

Once upon a time (not so long ago, 2012, in a certain esteemed tome which
costs $125), about 15 species of monkeyflower were submerged under the name "Mimulus guttatus". Such a broad treatment is equivalent to submerging species of pine as distinct as Monterey Pine (Pinus radiata), knobcone (P. attenuata), and Bishop Pine (P. muricata) into one species. For these pines, this is the viewpoint circa 1880. Ignorance is not bliss in the realm of biodiversity conservation. Many monkeyflowers are rare endemics, and our
understanding of their distribution and abundance is primitive.

Erythranthe guttata sensu stricto is a perennial with stolons. Within Section Simiola, most species have a
feature of the calyx after pollination that is distinctive. In flower, the calyx lobes are of two size
orders: the upper is longer, the other 4 are about equal. Following anthesis, in E. guttata, the lower
two calyx lobes curve upwards, accompanied by an expansion of the inter-calyx
rib tissues.

We have all seen the touch-receptive stigma of a monkeyflower (or if
not, ought to...). The pollination trigger
mechanism in this instance involves a set of genetic instructions independent
of those related to fruit maturation. Fertilization
triggers more than one genetic regulatory pathway: 1) quick, make seeds, and 2)
even quicker, make the calyx differentiate.
How?

Thursday, August 15, 2013

Federal Listing of rare plants in California has been in a log-jam for over
a decade. Over the last dozen years,
only three plants have been added to protection under the Endangered Species
Act. The 1990s was a period when listing
activity increased dramatically. Over
the past dozen years, listing has remained essentially static. Endangerment threats to the California flora
have been increasing over this period.

The recent, August 2013, proposal to list Ivesia webberi is the most
recent activity. Listing of this single
taxon does not break the jam. It
actually just highlights a dozen year moratorium – a fact that in practice
demonstrates that listing actions are a political and not a biological process.

On a biological basis, perhaps something on the order of 400 species of
California plants quality for Federal listing, about twice the number presently
listed.

Saturday, August 10, 2013

I hereby record that I did not relocate a Polemonium at Crater Lake, on
the western flank of Boreal Ridge, Nevada County (ca. 7500 feet
elevation), visited on Friday last. The terse label on the
specimen suggests that it was gathered on an ascent to the lake from Norden, to
the south. I obtained Crater Lake by
driving to the summit of Boreal Ridge, thence to the lake and vicinity from the
ridge proper.

The immediate vicinity of the Crater Lake is an odd geologic setting in
that the andesite (?) locally forms blocky (ca. 2 dm average diameter) patches
largely barren of vegetation – not unlike typical habitat for the tufted-alpine
polemoniums (Grant 1989)

The record CHSC3180 filed as Polemonium eximium is worthy of more study.

First, the elevation of this record is an
extreme low-elevation outlier, being located several thousand feet in elevation
below the lowest known records for Polemonium eximium, which as you know is one
of the highest-elevation limit vascular plants in the Sierra Nevada alpine.

Secondly Polemonium CHSC3180 has the membranous/chartaceous leaf bases
which characterize P. chartaceum and its sister taxon P. eddyense, which are poorly developed in P. exemium

Third, the geographic location is essentially distant from either
taxon, in being removed ca. 130 km from
the population of P. chartaceum (proximal in the Sweetwater Mountains, Mono
County), or, 300 km from P. eddyense on Mt Eddy, largely on the Siskyou County
side, in far northwestern California.

An ascent and search from Norden is suggested. My working hypothesis is that CHSC3180 is the
sole collection of an undescribed taxon in the P. chartaceum-P. eddyense clade,
geographically and mid-Pleistocene era isolated from its congeners.

Saturday, August 3, 2013

Shield-bracted monkeyflower (Erythranthe glaucescens (Greene) G.L.
Nesom) is on CNPS List 4 and is narrowly endemic to the Cascade Range foothills
of Shasta, Tehama and Butte Counties, California (a CNPS report from Colusa
county is not supported by a specimen).

Erythranthe glaucescens has been
variously described as either annual
(Thompson 1993, 2012) or as also perennial (Nesom 2012). Nesom
(2012, p. 61) noted this discrepancy with the notation that all but two
specimens were annual :

“Plants from one
locality produced filiform, small-leaved runners from basal cauline nodes:
California. Butte Co.: Canon of Big Chico Creek, 26 Mar 1914, Heller s.n. (MO)
and 2 Jul 1914, Heller s.n. (MO). Mcnair did not say what observations led him
to interpret the duration of E. glaucescens as perennial.”

Here I note that there are indeed perennial plants which are within the
current circumscription of Erythranthe glaucescens, and more specifically, that
there are likely to be two natural taxa involved, which implies that one taxon
is not yet described.

Plants of Erythranthe glaucescens
at JEPS109856 are clearly perennial: they produce abundant stolons. In this botanical sense, stolons are stem
organs which grow at the soil surface, or just below ground, which can also
form adventitious roots at the nodes, and which proliferate laterally from a parent
individual. Stolons are commonly
called runners (as used also by Nesom 2012).
By contrast, rhizomes are root tissue and mimic the same lateral expansion
model (and are not involved here).

My review of specimens and photographs of Erythranthe glaucescens suggest to me that two taxa are being
labeled as Erythranthe glaucescens. If I were to venture a key to the Calphotos
photos, it would be:

These differences are readily seen in the isotype (CAS792) which is
well preserved, and annual, vs. my specimen JEPS109856 which is clearly a stolonifrous
perennial. The images are above (face
of the diversion dam [upper photo, June 28 2006) and specimen (lower photo) in vivo collected there on 1 August 2013. In my initial primitive analysis, there seems
to be an elevation and habitat separation between the two putative taxa: glaucescens is a vernal stream or seep annual
of the foothills, while the undescribed taxon is a seepage-cliff specialist of
conifer forest settings at mid-elevations.

References:

Thompson, D. 1993 et 2012. Mimulus, in the Jepson Manual (2 eds.)

Neosm, G. Taxonomy of Erythranthe sect. Simiola (Phrymaceae) in the USA and Mexico.